Double wire wrap connection of juxtaposed terminals



E. T. DERKAS Nov. 17, 1964 DOUBLE WIRE WRAP CONNECTION OF JUXTAPOSED TERMINALS Filed Dec. 26, 1962 United States Patent YO ima 3,l57,734 DUBLE WIRE WRAP CONNECTIN F JUXTAIGSED TERMINAIS Ernest T. Berlins, Chester County, Pa., assigner to Philco Corporation, Philadeipliia, Pat, a corporation ot Delaware Filed Dee. 26, 1962, Ser. No. 247,152 5 Claims. (Ci. 174-33) This invention relates to electrical connector systems and to novel ways of producing the same. It provides closely associated connections, especially with wire-wrap contacts, and also provides concurrent establishment thereor". The new technique can be used for instance to connect a signal carrying wire with one terminal post while concurrently connecting a shield wire with a closely adjacent terminal post. While of broader utility, the technique has particular application to systems and operations wherein twisted pairs of wires are used and where the circuit carrier or support structure is of the printed circuit type.

It has long been desired to improve the construction of closely associated electrical connections. Rapidity of operation has been desired, along with firmness of resulting connector structures. Another object is to provide electrical connections in extremely crowded areas of a circuit panel. These and other objects, to be noted hereinafter, are promoted by the technique disclosed herein, which provides a pair or series of connector posts, one closely adjacent and parallel to the other, with a peculiar pattern of insulation and exposure of bare metal on said posts and with a special way of concurrently wrapping bare and insulated wire end portions on this pair of posts. This will now be described in greater detail with reference to the drawing appended hereto, wherein:

FIGURE 1 is a greatly enlarged, fragmentary, perspective view of an upper end portion of one of the pairs of connectors as it appears initially. FIGURE 2 is a view of a completed lug and wire structure, the orientation of this View being similar to that of FIGURE 1. FIGURES 3, 4 and 5 are sectional views taken respectively along lines 3 3, 4-4, and 5--5 in FIGURE 2. FIGURE 6 is a highly schematic representation of the lug and wire elements, indicating the concurrent operations performed thereon. FIGURE 7 is a fragmentary plan view of a circuit panel with the newly formed lug units thereon and FIGURE 8 is an edge view of this panel.

As indicated in FIGURE 1, a connector unit 2o is initially provided which comprises a plurality and particularly a pair of posts or lugs 21, 22, each desirably of rectangular cross section. A irst lug 21 is of relatively long upward extension and comprises a metallic core 23, with a coating of electrical insulation 24 surrounding the outside of a lower portion of this core, while the other lug 22 is relatively short and consists entirely of uninsulated metal.y rEhe two lugs are closely juxtaposed so that a side surface of the short or bare metal lug lies against a side surface of the insulation on the longer lug. This insulation of the iirst lug 2l extends upwardly to a point slightly above the upper end of the adjacent, e

shorter, bare metal lug 22. Metallic core 23 of lug 21 extends further upwardly from this point, beyond insulation 24. Lowerrnost'portions of lug unit 2% are soldered to a circuit board or the like, as schematically indicated VAin FIGURE 8 at 2S.

The new technique involves concurrent wrapping of a pair of wires 3l, 32 on this pair of, lugs 2i, 22 to produce the structure, shown in FIGURE 2, wherein metal of Wire 31 contacts metal of lug 21 while metal of Wire able tool of the wire wrapping type, not shown. In either ice case distinctive interrelationships of the two Wires and two lugs are established in accordance with the invention, as best shown in FIGURES 3 to 5. The individual method steps involved in the establishment of these arrangements are analyzed schematically in FIGURE 6.

With reference to FIGURES 2 and 6 it is to be noted that the two wires 31, 32 have, respectively, wire cores 33, 34, with insulations 35, 36 thereon, and that they have terminal portions 37, 38 extending in parallel untwisted strand form, whereas the body of the two wires, other than these terminal portions, desirably extends as a twisted strand. Terminal portion 38 of short wire 32 is shown as being entirely stripped of insulation, whereas only a final part 37 of the other terminal portion 37 is stripped to expose bare metal of the longer wire core. rIhus it will be seen that the shorter, bare terminal portion 3S and a juxtaposed, insulated part of longer terminal portion 37 are wound on the lower surfaces of the pair of lugs, which surfaces expose insulation of lug 21 on one side and metal of lug 22 on the other side, whereas metal 37 of the longer terminal portion 37 is wound on the uppermost, bare metal end of lug 21.

Referring more particularly to the method of producing the lower portion of the new wire wrap structure shown in FIGURE 2, the structure can be produced by simultaneously winding bare metal of short wire portion 38 and insulated parts of long wire portion 37 around the two lugs, thereby alternately contacting these wire elements (FIGURES 3 and 4, respectively) with insulated portions of the longer lug 21 and with bare metal of the shorter lug 22. In this way the metal cores of ground and signal wires 31, 32 are contacted respectively and selectively with lugs 2l, 22. Although the two lugs, as Well as the two wires, are closely juxtaposed, no metal contact is made between lug 2l and wire 32, or between lug 22 and wire 31. The selective contacting operations are performed substantially simultaneously, and also within most narrowly limited space, thereby greatly facilitating performance thereof when circuit components and terminals are closely packed on a wiring panel or circuit structure.

Referring in more detail to FIGURES 2 to 6, it will be seen that the shorter wire 32, which can for instance serve as signal wire, is here illustrated as having terminal core portion 3S bent into four or tive wire coils surrounding the pair of lugs, each of these coils having two points or areas of metal contact with the bare terminal 22, at points which appear at the right side of FIGURE 4. The parallel portion 37 of the other or ground wire 31 extends and curves along with the so connected signal wire. This second wire makes no contact with the bare metal of terminal 22, by virtue of the wire insulation 35, FIG- URE 3. The resilience of such insulation, along with the resilience of lug insulation 24, contributes advantageously to the firmness of metal-to-metal contact, established at successive corners of bare wire metal 3S, FIG- URE 4.

In the very schematic illustration of FIGURE 6, distinctive symbols are used along the surfaces of lug 20 to represent different types of contact. Metal-to-metal contacts are here indicated by small black dots, contacts of metal with an insulator are indicated by large black dots, and mutual contacting of insulated elements is indicated, on these surfaces, by the use of double circles concentrically drawn. It will be seen that the first and lower vphase of the new wire-winding operation involves (I) as to bare wire portion 38, successive steps of'(l) establishing metal-to-metal contacts (see the small dots on 22) and metal-to-insulation contacts (see the outer large dots, on 2t), concurrently with (II) successive establishment of metal-to-insulation contacts (inner large dots, on 22) and of insulation-to-insulation contacts (open circles on 2l), for section 37 ofiusulated wire 31. In a nal and upper phase, ordinary metal-to-metal contacts are made for terminal portion 37. of this wire 31 (small dots).

As indicated in FIGURE 7 it is possible by this new technique to. connect wire pairs 51, 52 withl lug units 53, 54t either at one endl of each wire pairy (51, 52)` or at both. ends thereof (156, 57). It is believed: to be unnecessary at this point to describe other features of the supporting circuit board 58: and additional electronic components 59, 601y thereon. 'I he new product or connector system, as best indicated by. FIGURES 2' and 6, is characterized in that paralleli longI andi short metallic lugs. (21, 22), closely juxtaposed but insulated from one. another (24.), haveadjacent long and short wires. (31', 32)- wound thereon with limited, selective metaly contact,y the metal 0f the shorty wire contactingl no metal but that of the short lug andi the metalI of the longwire contacting no metal but that of the long: lug. By meansof such arrangement, doubleor multiple wire connections can. be made in circuitl panel areas of' unprecedented smallness.

Whileonly` asingle embodiment of the invention has been' fully described; the details thereof are not to be construed aslimitative of the invention. The invention contemplates such variations and modications as come within the scope of theappended claims.

I claim:

1 .v A double wire-wrap structure comprising:

a, pair of parallel and closely adjacent, metallic posts,

onelonger than andinsulated from. the other; and

ai pair of wires,- one longer than and, insulated from;

theA other v vireinsu1atedl from the shorter post and wire-wrapped on an, end portion, of the longer post toI makel electrical connection between said longer wire and longer post,A both; wires being` wrapped' around the pair ofy posts below said end portion,

and theshorter wire being'insulated. from the longer post and in wire-wrapy contact withv the shorter post tomake` electrical connection between said shorter wire and shorter post.

2. A structure as described in claim l, including insulative material surrounding the longer post below said end portion thereof to provide the insulation of the longer post from the shorter post and from the shorter Wire.

3. In a multiple electrical terminal structure:

a system of parallel, juxtaposed, rigid metallic lugs insulated from each other, comprising rst and second lugs; and

a system of juxtaposed, iexible metallic conductors extending along portions of each other and around the system of rigid lugs, the first flexible conductor being insulated from the second rigid lug and being electrically connected With the rst rigid lug, and the second iiexible conductor being insulated from the first rigid lug and being electrically connected with the second rigid lug.

4. Ina structure as described in claim 3, the feature that said lugs have rectangular cross-section with sharpr corners for deforming metal of theconductors.

5. An, electrical connector structure for signal and ground wires and the like, comprising:

a relatively tall metallic lug with an insulative coating around a lower portion thereof;

a relativelyl low metallic lug iny contact and parallelism with saidl coating;

a relatively long wire having an exposed metallic core as an end portion thereof and having insulative material around ak preceding wire portion, said wire being woundl around both lugs withy said insulative material contacting said insulative coating and rela.` tively low metallic lug, said corevv contacting` said` relatively tallY lug above said coating to electricallyA connect said relatively long wire withY said relatively tall lug; andV a` relatively short wire, having an exposed metallic core as an end portion. thereof wound around both iefereneesited, in the tile of this patent UNITED STATES PATENTS.

Reck Aug. 8, 1961V Wynia etal Dee. 12; 196,1 

3. IN A MULTIPLE ELECTICAL TERMINAL STRUCTURAL: A SYSTEM OF PARALLEL, JUXTAPOSED, RIID METALLIC LUGS INSULATED FROM EACH OTHER, COMPRISING FIRST AND SECOND LUGS; AND A SYSTEM OF JUXTAPOSED, FLEXIBLE METALLIC CONDUCTORS EXTENDING ALONG PORTIONS OF EACH OTHER AND AROUND THE SYSTEM OF RIGID LUGS, THE FIRST FLEXIBLE CONDUCTOR BEING INSULATED FROM THE SECOND RIGID LUG AND BEING ELECTRICALLY CONNECTED WITH THE FIRST RIGID LUG, AND THE SECOND FLEXIBLE CONDUCTOR BEING INSULATED FROM THE FIRST RIGID LUG AND BEING ELECTRICALLY CONNECTED WITH THE SECOND RIGID LUG. 